Method of making closed-end tubes.



L. E. HOOKER.

METHOD OF MAKING CLOSED END TUBES. APPLICATION FILED NOV. 20, 1909.

934,174. Patented Sept. 14, 1909.

Sywewtoz LEfl'aoker'" UNITED STATES PATENT ,OFFIGE.

LESLIE E. HOOKER, OF PAWTUCKET, RHODE ISLAND.

METHOD OF MAKING CLOSED-END TUBES.

To all whom it may concern:

Be it known that I, Lnsmn E. Hookah, a citizen of the United States, residing at Pawtucket, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Methods of Making Closed-End Tubes, of

whiclrthe following is a specification. My, invention relates to the manufacturev .ot' closed-end tubes, by which I mean tubes which have one end closed and which are adapted for various uses, for example, as detonator tubes or blastin sists in an improved method tubes. tubes. closed at one end to contain the tulminute, and attached to the fuse at the open end, and are set into the end of a dynamite or other blasting cartridge. Heretofore, they of making such have been made by a succession ot'drawing operations, the metal being sometimes weakened near the junction of the wall and the closed end so that the latter will bev blown o'l'l when the fulminate is exploded.

My invention consists in closing the end of an open tube by crimping in the wall at that end'and then compressing the crimped or fluted portion so as to make the end smooth with no perceptible break in the continuityof the metal but yet leaving'it so it will readily open outward under lnternal pressure.

caps, and coni These tubes or caps are short metal i v Specification at tenets '1 atent. Patented Sept. 14,1909. Application inea 'figvemte'r '20, 1908. Serial No. 463,581.

plunger 11, causingitto assume the shape, or rather the reverse of the shape of the top 14 of said plunger. Thetube is then in the condition illustrated in. Figs. 2 and 3, its end being nearly closed by the crim led portion 3. The tube 2 is thenrremove'd rornthe die and placed with its crimped end in the smooth, shallow. recess or die 15, and the correspondingly-shaped punch 16 isbrought down inside it. Of course the tube'niay instead be first slipped on-the punch and then the latter brought down into the "recess or die 15. By the pressure between this punch and die, the crii'nps 3 in the end of the tube are compressed or flattened out," the metal being forced to assume asmooth flat condition, infact, flowing both radially and inwardly, the latter how completely closing the central aperture. T he end of the tube l, thus produced, see Figs. 4 and 5, is practically air-tight, without being actually welded, so that it .is in condiion to. open outwardly under internal pressure whenthe charge of fulminate conta ned therein is.igmied. thus letting the ex lOSlOIl pass Cll rectly into the dynamite o the cartridge.

Other uses of my improved tube .will

readily suggest themselves.

Having thus described my invention. What- I claim, is

The method of making a closed-end tube,

; which consists in taking an open-ended tube In the accompanying drawing, Figures 1 5 inclusive show the different steps of the method. Figs. (3, and 7 show dies 111 which said method may b carried out.

I take thin coppe j tubes, preferably made by the extrusion method, and saw them up into suitable lengths, thus obtaining the tube 1. open at bot-blends, shown in Fig. 1. I place this tube in the die 10, shown in Fig. (3, the end of the tnbe resting on the plunger 11, the top of which is crimped or fluted, as shown at 14 in Fig. 7. The punch 12 is 1 then brought down into the tube, its shoulder 1?) engaging the top of the same, and torc'es the lower end downwardly onto the and first crimping in one end of it by forcing said end into a concave, crnnpedor fluted die, and secondly, smoothing .out. said i i i l i crimped end by pressure between a smooth concave die and a smooth convex punch.

whereby said end is tightly closed but is. in

condition to readily open outwardly under internal pressure.

In testimony whereof I'have atflxedmy signature, in presence of two witnesses.

LESLIE E. HOOKER.

Witnesses HARRY A. Yn'r'rnn, CORTLAND WJLBER. 

